1. Field of the Invention
The invention relates to a brake caliper for a disk brake, having a caliper housing in which an actuating device having a piston in a bore is provided. Said piston is mounted so as to be movable in the bore along a bore axis, with a movement being possible in each case in an application direction and in a return direction. A sealing arrangement having a sealing ring in a radial groove is provided between the piston and the bore.
2. Description of the Related Art
A brake caliper of a disk brake is known from EP 0 403 635 B1. Said document specifies a combined brake caliper for a motor vehicle disk brake, which brake caliper comprises a caliper housing in a bore in which a piston for actuating the brake is arranged in a movable fashion. To provide a parking brake function, a shaft is rotatably mounted in the caliper housing, with the shaft extending through the caliper housing and being connected to a ramp element of a ramp arrangement. Between the piston and the bore, a sealing ring is arranged in a groove, which sealing ring is intended to prevent pressure medium for the hydraulic actuation of the disk brake from escaping. It has been found that the present sealing arrangement has considerable disadvantages for comfort and for the wear of linings and friction rings, since only an unsatisfactory return movement of the piston with the brake lining takes place, and an insufficient air play can be generated between the brake lining and the brake disk. As a result of brake linings bearing against the brake disk when the disk brake is not actuated, a braking residual torque is therefore generated which increases fuel consumption and leads to noise being generated and to excessive wear of the brake linings and of the friction rings. The stated disadvantages are particularly severe if the brake is mechanically actuated, since the return movement caused by the sealing ring is reduced.